Such containers, in particular mascara containers, conventionally comprise a wiper provided close to the neck of the container (in practice on the reservoir), which is adapted to keep back the excess product taken by the applicator each time it is plunged into the reservoir, into the mass of product.
In practice the application member comprises a cap which the user acts upon to manipulate the mascara applicator. The fact that the mascara is liquid or pasty means that efficient sealing must be provided outside periods when mascara is applied, when the cap is engaged on the neck of the container; in practice this sealing is obtained by a closure by screwing or by clip action of the cap onto the neck of the container. It follows that the cap is a member which forms a substantial part of the outside surface of a mascara container in closed configuration, and that combined movements or significant forces may have to be provided to open the container before an action to apply mascara.
Document EP-1 721 543 describes various containers for cosmetic product, including a container of mascara (or even of gloss in relation with FIGS. 18 to 24) comprising:                a body which is elongate in a longitudinal direction and provided with a bottom and a free edge,        a reservoir contained in that body and movable in translation between a low stable position and a high stable position, the reservoir comprising a neck,        an elastically compressible device with two stable retraction positions which is disposed between the body and the reservoir and of which the two stable axial retraction positions define the two stable positions, low and high, of the reservoir,        an application member comprising a shaft terminated by an applicator adapted to be loaded with mascara, this application member having a resting configuration in which a part of the shaft and the applicator are contained in the reservoir so as to enable the applicator to be loaded with mascara, and being able to leave that resting configuration until it is completely out of the reservoir and of the container,        a cap joined to the shaft of the application member and adapted to engage within the body, the stable axial retraction configurations of the elastically compressible device being such that when the application member is in its resting configuration in the reservoir, the cap is either retracted into the body flush with the free edge of the body, or it projects at least partially from the body,        a wiper provided at the exit of the reservoir so as to be passed through by the applicator when it enters the reservoir or when it is extracted out of it, and        complementary sealing members respectively carried by the shaft and the neck of the reservoir constituted by a protuberance carried by the shaft and anchoring claws provided on the neck of the reservoir (in the high position of the reservoir, the claws spread outside the inside volume of the body in which the reservoir slides, whereas in low position, the claws are maintained in a brought-together configuration by the inside wall of that body so as to remain engaged on the protuberance).        
Such a configuration is simple and reliable in use without significant risk of inadvertent opening, while making it possible to have very sleek aesthetics, and without leading to prohibitive voluminosity.
More particularly, the retraction of the cap into the body of the container enables the aesthetics of the container to be essentially defined by that body, while the presence of the elastically compressible device with two stable retraction positions enables a mere movement of pushing in of the cap, transmitted to the reservoir, to give rise to the passage of that device from one retraction position to the other, and leads either to the retraction of the cap (there then is very little risk of the cap inadvertently getting out of the body), or to a part of that cap coming to project sufficiently to enable that projecting part to be grasped between the fingers of a user then its extraction out from the body to perform the application of the product taken by the applicator (which only requires the user to make movements that are simple, with a single hand).
It should be noted that, in such a container, the reservoir is movable between two main positions which are essentially defined by the elastically compressible device:                a low position in the body (enabling the cap to be flush with the free edge of the body), when the application member is in its resting configuration, that is to say that the elastically compressible device is in the most retracted of its stable configurations, and        a high position in which its neck is substantially at the level of that free edge (to enable the separation of the complementary sealing members), defined by the most elongate of the stable configurations of the elastically compressible device.        
The sealing members remain in cooperation while the reservoir is situated between these extreme positions, even when the cap has started to come out from the body.
Thus, not only is the use of such a container simple and reliable, but such a container furthermore has good sealing characteristics, without however requiring complex movements by the user, but at the cost of a certain complexity of structure.
It is to be noted that, independently of the aesthetic effect which enables the retraction of the application member into the body, an advantage of the fact that this application member can engage telescopically in the body is to enable good ergonomics to be obtained by the choice of axial dimensions of the cap of the application member and of the body (the greater these dimensions, the easier it is for a user to manipulate that cap and that body) without those axial dimensions determining the bulk of the container, in resting configuration (the greater the telescopic engagement of the application member in the body, the smaller the axial bulk).